Return error if opened in mono mode cuz not supported.
Add support for Pa_GetCPULoad();
Fixed timestamp in callback and Pa_StreamTime() (Thanks n++k for the advice!)
Check for invalid sample rates and return an error.
Check for getenv("PA_MIN_LATEWNCY_MSEC") to set latency externally.
Better error checking for invalid channel counts and invalid devices.
fixed isInput so GetProperty works better,
fixed device queries for numChannels and sampleRates,
one CoreAudio device now maps to separate input and output PaDevices,
audio input works if using same CoreAudio device (some HW devices make separate CoreAudio devices).
